THE RESULTS OF HYBRID TOTAL HIP ARTHROPLASTY

Abstract

Introduction: The aim of this study was to evaluate patients who were treated with hybrid total hip arthroplasty (THA) and to determine the effects of the surgical techniques utilized and prosthesis designs on the results.
Patients and methods: Between March 1990 and Nowember 2001, 188 hips of 168 patients (118 of whom were women and 50 were men) treated with THA were evaluated. The average age of the patients was 59.4 years (26-85). 84 patients were treated for their right hips, and 64 for left. 20 patients were treated for both hips. The major causative agent was primary osteoarthritis (68.6%). While direct lateral approach was used in 110 hips (58.5%), posterior approach was preferred for the other 78 (41.5%). Collar design of prosthesis was used in 79 cases (42.0%) and collarless design of prosthesis was used in 109 (58.0%). The cases were evaluated clinically with Harris hip criteria, radiologically via the radiological evaluation criteria of Johnson and et all, and for heterotopic ossification according to Brooker’s classification. The cases were statistically evaluated via the paired-t test, Fisher-exact test and ?-square test.
Results: The average value of Haris hip score was 38.0 at the preoperative period and it was 92.5 by the end of the avarege follow-up of 37.5 months. In 170 hips (90.5%), clinically excellent or good results were achieved. The problem of acetabular cup was detected radiologically in four cases (2.1%), femoral loosening in four cases (2.1%) and they were operated for revision. Eight patients (4.2%) were advised for revision operation due to femoral loosening. By the end of the avarege follow-up of 37.5 months; 8.5% of the 188 hips were radiologically found to be warranting revision operation.
Discussion: In this study, although the clinical results were similar with those in the literature, the problems about femoral component were radiologically apparent. In these cases, cementing techniques utilized turned out to be the major factor and modern cementing techniques should be applied for femoral component in all conditions.